How many grams of magnesium (mg, 24.30 g/mol) are in 7.43x10^22 atoms of mg?

Given the number of Mg atoms is

We know that 1 mol of any substance has Avogadro number of formula units.

Converting number of atoms to mol:

Converting mol to mass of Mg:

Therefore mass of Mg is 2.99 g

the equation that correctly represent the reaction for formation of ammonia is

n2+ 3h2 → 2nh3 (answer d)

1 mole of nitrogen gas (n2) react with 3 moles of hydrogen gas (h2) to form 2 moles of ammonia ( nh3). this is in a process known as haber process were iron is used as a catalyst and reaction take place that a higher temperature and pressure. the process is exothermic hence energy is released.

i'm assuming that the correct answer is indeed the first one/ "a"..